malloc/mpool.h

   1 #include <sys/queue.h>
   2
   3 #define MPOOL_DEBUG
   4 #define MPOOL_STATS
   5
   6 #ifdef MPOOL_DEBUG
   7 #define DPRINTF(a) printf a
   8 #else
   9 #define DPRINTF(a)
  10 #endif
  11
  12 #define NODE_AVAIL  (1 << 0)    /* If not set, node is reserved, else available */
  13 #define NODE_LR     (1 << 1)    /* If not set, node is left buddy, else right buddy */
  14
  15 typedef struct blknode {
  16     unsigned char flags;    /* availability and left-right buddiness */
  17     size_t logsize;         /* logarithm of size with base 2 */
  18     void *ptr;
  19     LIST_ENTRY(blknode) next_block;
  20 } blknode_t;
  21
  22 typedef struct mpool {
  23     void *mem;
  24     size_t nblocks;       /* nblocks = logsize + 1 */
  25     size_t maxlogsize;    /* logarithm of maximum size of chunk with base 2 */
  26     size_t minlogsize;    /* logarithm of minimum size of chunk with base 2 */
  27 #ifdef MPOOL_STATS
  28     size_t nsplits;       /* number of splits made */
  29     size_t nmerges;       /* number of merges made */
  30 #endif
  31     LIST_HEAD(blkhead, blknode) *blktable;
  32 } mpool_t;
  33
  34 typedef struct blkhead blkhead_t;
  35
  36 typedef enum {
  37     MP_OK,
  38     MP_EBADVAL,
  39     MP_ENOMEM
  40 } mpret_t;
  41
  42 /* Function prototypes */
  43 mpret_t mpool_init(mpool_t **mpool, size_t maxlogsize, size_t minlogsize);
  44 void *mpool_alloc(mpool_t *mpool, size_t size);
  45 void mpool_free(mpool_t *mpool, void *ptr);
  46 void mpool_destroy(mpool_t *mpool);
  47
  48 void mpool_printblks(const mpool_t *mpool);
  49 void mpool_stat_get_nodes(const mpool_t *mpool, size_t *avail, size_t *used);
  50 void mpool_stat_get_bytes(const mpool_t *mpool, size_t *avail, size_t *used);
  51 #ifdef MPOOL_STATS
  52 size_t mpool_stat_get_splits(const mpool_t *mpool);
  53 size_t mpool_stat_get_merges(const mpool_t *mpool);
  54 #endif